Does it ever make sense to config a kernel using "make i386_defconfig" on a typical desktop PC?

What I noticed was that, using the 'defconfig' option, I ended up with a modules.dep file with only three entries. The default (previous) modules.dep had many, many entries (maybe 1000 or so?) Repeating the entire process starting with 'make mrproper' followed by 'make oldconfig' yields a very different result.

I have a hunch "make i386_defconfig" was where I went wrong.

i386_defconfig doesn't include that much. Normally you should look into the options and enable the support/functionalities you need. With i386_defconfig you may be missing drivers for some of your hardware, for example.

Hi, thanks for that reply. Trouble is, how does one know which support one needs for a typical desktop PC? I dare say even an expert would struggle at this, even if he/she knew the system hardware in great detail. For my part, I was only successful after doing make oldconfig first. But that depends on there being an existing .config file to start from. So how does this chicken-and-egg cycle get started?

One good idea is to boot up one of those "all on one DVD" distros, e.g. Knoppix, and note what drivers it auto-detected and ran.

Note how it described the hardware, what drivers it selected and so on. This should be "a configuration that works." It might not be the one that you finally select but it is a good starting point for an unknown machine. (Attach whatever USB devices you have and note also how they are detected.)

It is much faster to do this auto-detection once, and to custom-build a kernel/module set that is "known good" for it, than to lumber through the detection process with every boot.

Just be sure to save a copy of the (hidden) .config file in a safe place, carefully labeled and dated (and un-hidden). Do this each time you change the system configuration. Keep careful records. Once you get the system configured the first time, getting it back to that known-good state should become a non-brainer; something that you have practiced and that can be done entirely by rote, following steps that you have actually written down and actually know how to get to in a crisis. (The git version-control system is quite a handy adjunct for this task, since it requires no server.)